Department of Transportation

Intersections Controlled By Traffic Signals

Traffic Signal Operations in the City of Pasadena

Currently, the City of Pasadena operates 300 traffic signals and 10 traffic surveillance closed circuit television cameras that allow personnel to monitor the traffic signals from the City's Traffic Management Center (TMC).

The TMC is equipped with an extensive communication system that allows City staff to view traffic operations at key locations as they actually happen and has allowed traffic operations to flow more smoothly as traffic demands change. The TMC's Traffic Control System and the Special Events Unit of the Pasadena Police Department share the responsibility of managing traffic for all Rose Bowl and street fair events.

The Importance of Traffic Signals in Pasadena

Traffic signals have become a valuable tool for ensuring traffic flow throughout the community. Some of the signals are timed to work with other traffic signals to allow continuous flow from one signal to another. Some are timed so that if you are driving at the posted speed limit, you will receive a green signal at each intersection as you progress down the street. Others are on preset timers where the red, green and yellow indications will cycle for a specified time period.

The goal of the Traffic Engineering Operations team is to provide the most comfortable ride as possible by getting the greatest number of vehicles through the system with the fewest stops. It would be ideal if every driver could drive without stopping from one destination to another. But we live in a real-world society rather than a vacuum and free flow is not possible even with the most intricate well-designed systems.

However, the City of Pasadena is always investigating new technology and methods to enhance traffic flow and has been awarded grants from the State of California and the County of Los Angeles to incorporate newfound technologies or techniques as a research project.

Traffic Signal Safety

Red Signal Indication

A red signal indication means that the traffic facing the indicator shall stop until the indication turns green.Although, right turns are permissible at most intersections after the driver has stopped, the driver must yield to pedestrians and vehicles in their path.The City of Pasadena has posted some locations where vehicles are prohibited from making any turns on red.The locations with NO TURN ON RED signs are posted for safety reasons and the driver should not make the turn until a green indication for the direction of flow is shown. Click here to view the Traffic Signals Brochure.

Reminder: Do not stop on the trains tracks even when the traffic signal is red! Your best action is to keep the tracks clear. Do not attempt to move forward if there does not appear to be sufficient room to clear the tracks.

Red Arrow Indication

A red signal with an arrow also means stop. A driver may not make a turn against the red arrow. The driver must wait for a green signal or a green arrow to make the permissible move.

Yellow Signal Indication

Yellow signals warn drivers that the signal will change to a red indication momentarily. If you have not already entered the intersection and can safely stop prior to entering it, stop and wait for the next cycle. If you are already in the intersection, proceed through the intersection.

Green Signal Indication

Green signals mean that the driver has the right of way at the intersection to proceed provided there are no other interferences (i.e. other vehicles ahead of your vehicle, pedestrians, emergency vehicles, etc.). Please note that if other vehicles are still in the intersection when the light turns green, the driver must yield to the vehicles and pedestrians and the driver must ensure that all traffic in the conflicting directions has stopped before moving ahead. If making a left turn, the driver can only make the turn if there is sufficient time and space to complete the turn before oncoming traffic becomes a hazard.

Do Not Cause Gridlock

Do not enter the intersection if the light is green and you will not be able to completely cross the intersection before the light turns red. You can be cited if you to block traffic in an intersection. Reminder: Do not stop on the trains tracks even when the traffic signal is green! Your best action is to keep the tracks clear. Do not attempt to move forward if there does not appear to be sufficient room to clear the tracks.

Green Arrow Indication

A green arrow allows drivers to turn while the arrow is green but the driver must still yield to pedestrians, bicyclists and any vehicle in its path. The green arrow is what traffic engineers call a “protected” turn because oncoming traffic is stopped while the arrow is green.

Flashing Red Indication

According to the California Vehicle Code, when a red lens is illuminated with rapid intermittent red flashes, a driver shall stop before entering the intersection and proceed according to rules established at a 4-way stop controlled intersection.

Flashing Yellow Indication

When a yellow lens is illuminated with rapid intermittent yellow flashes, a driver may proceed through the intersection with caution.

Traffic Control Officers

Any time a peace officer is directing traffic, motorists must obey the officer regardless of the indication of the traffic signal.

Traffic Signal Blackout or “Dark” Signals

When traffic signals at an intersection are not operating due to a power failure, all drivers must stop before proceeding through the intersection and follow the same rules as a 4-way stop controlled intersection.

Traffic Signal Equipment

Traffic Sgnals consist of the following main components:

Traffic Signal Controller

Signal Heads (typically with red, yellow and green faces)

Vehicle Detectors

Traffic Signal Controller

The traffic signal controller is the means of changing the signal indications and consists of computer controls that operate selection and timing of traffic movements in accordance to pre-programmed sequences and vehicle detection.

Signal Heads

A signal head consists of one or more signal faces that can include solid red, yellow or green lights and faces with turn arrows using one or more of the same colors.

Vehicle Detectors

The City of Pasadena uses a combination of in-pavement loops and cameras to detect vehicles in the intersection to determine whether a vehicle is present.

Red Light Running and Traffic Enforcement

Unfortunately, there are drivers who tend to push the limit on “making” the traffic signal by running red lights and thereby causing a danger to others that may be entering the intersection. Red-light running is a serious intersection safety issue across the nation. According to the National Highway Traffic Safety Administration’s (NHTSA) Traffic Safety Facts 2008 Report, there were more than 2.3 million reported intersection-related crashes, resulting in more than 7,770 fatalities and approximately 733,000 injury crashes. For this reason, the busiest signalized intersections in the City of Pasadena are equipped with special devices to assist the police department to manually cite red light running violations. It has been demonstrated in numerous instances that effective and consistent enforcement of all traffic laws such as basic speed law, red light running and others has a positive effect of reducing overall traffic crashes.